Robert J. Havighurst was an influential American developmental psychologist and educator who developed a theory of human development and identified developmental tasks occurring at different life stages from infancy to old age. He recognized that developmental tasks arise from physical maturation, personal values, and societal pressures. Some key developmental tasks he identified included learning to walk and talk in infancy, getting along with peers and developing gender roles in childhood and adolescence, selecting an occupation and starting a family in early adulthood, assisting teenage children in middle age, and adjusting to retirement and reduced mobility in later life. Havighurst stressed the importance of teachers helping students accomplish developmental tasks appropriate for their age.